Public policies that affect alcohol consumption and related behaviors can influence a range of health and social outcomes. Advances in scientific research on the effects of various alcohol-related policies depend on well measured indicators of these policies. Research in this important area has been constrained by limitations on the availability and quality of policy information. Initiatives to provide reliable information on public policies relating to alcohol must contend with the extraordinary complexity of alcohol policy in the United States. Laws, regulations, and jurisprudence address myriad aspects of alcoholic beverage production, packaging, transportation, marketing, taxation, sales, and consumption, as well as the financing and delivery of alcohol related treatment and preventive services. Many of these policies are established by governments at all levels (Federal, State, county, and municipal). The National Institute on Alcohol Abuse and Alcoholism (NIAAA) developed the Alcohol Policy Information System (APIS) to provide authoritative, detailed, and comparable information on alcohol-related public policies in the United States at both the State and Federal levels. The APIS website (http://alcoholpolicy.niaaa.nih.gov) is an online resource that provides public access to this detailed information on a wide variety of alcohol-related public policies. APIS features compilations and analyses of alcohol-related statutes and regulations. APIS is designed to simplify the process of ascertaining the state of the law for studies on the effects and effectiveness of alcohol-related policies. APIS currently provides information on 36 specific policy topics, including summary descriptions, maps, detailed comparison tables, and the specific dates on which provisions became or ceased to be effective. APIS is intended to be of primary use to researchers seeking to study the effects and/or effectiveness of alcohol-related public policies, either singly or in combination. In keeping with the project goal of supporting and encouraging such research, information delivered through the APIS web site aims to facilitate reliable and valid comparisons of policy status both across jurisdictions and overtime. The APIS project contributes to the mission of the NIAAA by providing data that support research to: (1) assess the effects of alcohol-related policies, both individually and in combination, on a wide variety of important health, social, and economic outcomes; and (2) identify and evaluate factors that enhance or inhibit the effectiveness of these policies.